2-Methylthio-imidazolins: a rare case of different tautomeric forms in solid state and in solution
作者:Venelin Enchev、Nadezhda Markova、Marin Marinov、Neyko Stoyanov、Marin Rogojerov、Angel Ugrinov、Iwona Wawer、Dariusz Maciej Pisklak
DOI:10.1007/s11224-016-0860-4
日期:2017.6
that the tautomeric form in solution is different from that one in solid state. The substantial difference between positions of the characteristic C=N band in nonpolar solvent and crystalline phase for both compounds suggests that in solid state a “conjugated tautomeric form” exists, while in solution phase there is “non-conjugated tautomeric form”. In polar solvents, both tautomeric forms exist. It
两种新化合物2-(甲硫基)-1,3-二氮杂螺[4.4]non-2-ene-4-one(1)和2-(甲硫基)-1,3-二氮杂螺[4.4]的合成及结构解析]non-2-ene-4-thione (2), 呈现。两种化合物均以单斜晶系结晶。化合物1为片状无色晶体,而化合物2为黄色针状晶体。两种化合物的结构和光谱特征通过红外和核磁共振光谱和量子化学进行研究。优化的几何形状、谐波振动频率和 NMR 屏蔽是通过 DFT 采用 B3LYP 函数计算的,使用 6-311++G(d,p) 基组。我们的结果支持在报告的晶体结构中观察到的氢键模式。给出的证据表明溶液中的互变异构形式不同于固态中的互变异构形式。两种化合物在非极性溶剂和结晶相中特征 C=N 带的位置之间的显着差异表明,在固态下存在“共轭互变异构形式”,而在溶液相中存在“非共轭互变异构形式”。在极性溶剂中,两种互变异构形式都存在。建议将这种现象称为d